Method of producing wire staples



Aug. 30, 1938. M. VOGEL 2,128,443

METHOD OF PRODUCING WIRE STAPLES Filed Aug. 20, 1956 iiiiilll I )0 l2 0 /Z ATTORNEY Patented Aug. 30,1938

UNITED STATES P E T I OFFICE Claims.

The ,present invention relates to wire staples and method of producing the same, and has for an object to provide a method by which staple strips may be formed economically and speedily, I and by which the means for causing the individual staples to adhere in the strip may be provided in a simpler and more reliable manner than heretofore.

It is particularly proposed to form staple strips by first winding a wire into a helix with the con-.

volutions of the helix forming the crowns and .side legs of two strips of staples, next providing means to cause the convolutions of the 'helix to adhere to each other, and then cutting two opposed sides of the helix along lines parallel to its axis to form the same into a pair of staple strips.

It has heretofore been proposed to form wire staples by winding wire in the form of a helix about a large drum, connecting the convolutions of the wire by rows of easily breakable material,

as solder, which rows were disposed in a direc-' tion parallel to the axis of the helix, then severing the convolutions at points between therows of breakable material to form strips of staple blanks and thereupon bending the staple blanks transversely into U-shape to produce staple strips. Such a method is disclosed in the U. S. patent to Josef von Vass, for Process of manufacturing staples, No. 1,169,698, dated January 25, 1916.

Whereas in this previous method the operation of bending the strips into U-shape was unrelated to and subsequent to the winding of the wire into a helix, in the present invention the operation of forming the helix also bends the strip forming portions of the wound wire into U-sha'pe staple form.

In the accompanying drawing I have illustrated the staple strips produced according to the invention and the steps employed in carrying out the improved method.

In the drawing:

Fig. 1 is a perspective view of a mandrel, and showing the wire in process of being wound into a helix about the mandrel.

Fig. 2 is a perspective view of a helically wound length of wire.

Fig. 3 shows the helically wound length of wire cut in half, the cut producing points upon the legs of the staple strips.

Fig. 4 shows the two staple strips,formed from the helically wound length of the wire, innested relation preparatory to packing.

Fig. 5 is an enlarged sectional view of several staples according to the invention and showing the manner in which they are caused to adhere together.

Fig. 6 shows a modified form of wire provided with a coating and prior tobeing treated to cause I the coating to adhere.

Fig. 7 shows the staples illustrated in Fig. 6

' after being treated to cause the coating to adhere.

Fig. 8 shows staples formed of circular section wire.

Fig. 9 is a sectional view of a modified form of mandrel and dies for imparting to th staple strip aparticular shape after winding of the wire.

Fig. 10 shows the two staple strips formed from the wound wire illustrated in Fig. 9.

Referringto' thedrawing the wire l0, which may be oi any suitable cross-section, as rectangu- 1 lar, circular."ovai or the like, is first wound about a mandrel Ii into the form of a helix, the wire being tightly and closely wound so that the convoiutions are "in contact. 7 1

The helically wound tubeof wire thusproduced is next treated to cause the convolutions to adhere, and this step may be carried out in several different ways. 'The tube maybe dipped in or sprayed with suitable adhesive as glue, lacquer or metal and then allowed to dry, it may be electrically plated with a thin deposit of metal causing the convolutions to adhere, or it may be provided with a thin solder coating or with strips of solder. Theadliesive means is indicated at l2 in Fig. 5. Due to the continuity of the wire forming the tube an electrical current may be passed through it either for eiectro-plating, or heating. In the latter case a wire provided with a coating ll, of lacquer, solder, or the like, as shown in Figs. 6 and 7, may be conveniently and uniformly heated to cause the coating to melt and connect the convolutions together, and at the same time to provide a protective covering against rust, or corrosion. As themethod permits the adhesive to entirely cover-the outer and inner surfaces and to enter between the convolutions the convolutions will be most effectually connected together. The helically wound staple strip forming tube, as shown in Fig. 2, lends itself to the convenient and eflicient application of the means for causing the convolutions to adhere, particularly as the wire is rigid and unbroken in this form and the tubes may therefore be handled in bulk without separation of the convolutions or distortion.

The next step consists in separating the helically wound tube into two staple strips by cutting the side portions along medial lines parallel to the axis of the tube, as shown in Fig. 3. This step 65 crossis preferably carried out by means of a cutting 'tool which, in addition to separating the strips,

will also produce points I l upon the staple legs, such a tool consisting for instance of a grinding disc l5, as shown in Fig. 3. The two staple strips formed from the helically wound tube will after cutting fall automatically into the nested relation shown in Fig. 4, and as such strips are usually packed in boxes in this nested relation it will be seen that the method also facilitates the handling and packing of the staple strips.

In Fig. 8 I have shown circular cross-section wire Ill This may be provided either with adhesive means after winding, or pre-coated as in staple strips are formed the modification Figs. 6 and 7.

In Figs. 9 and 10 I have shown the method by which staples having an arcuate crown and inwardly converging side legs are produced. The wire in is helically wound about the mandrel it in a substantially similar manner to the winding illustrated in Fig. 1, the mandrel having a crosssectional shape corresponding to the shapes of the two opposed staple strips to be formed. After winding the side legs are pressed inwardly by suitably shaped dies l'l. Thereupon the two by first providing the wire with adhesive means and then cutting the helically wound wire tube along the medial lines of the sides. It will be understood that any desired shapes may be imparted to the staple strips in a substantially similar manner to that illustrated in Fig. 9.

While I have illustrated a preferred method of carrying out the invention and preferred forms of staple strips it will be understood that the same may be varied without departing from the spirit and scope of the invention Having thus described my invention what I claim and desire to secure by Letters Patent is:

, 1. The method of producing staple strips which consists in winding a length of wire into a helix having a plurality of staple bridge forming sides and a plurality of staple leg forming sides angularly bent with respect to said bridge forming sides along bending lines parallel to the axis oi said helix, causing the convolutions or said helix to adhere, and cutting said helix along said leg forming sides on cutting lines parallel to the axis of said helix to form a plurality of staple strips from said helix.

2. The method of producing staplestrips which consists in winding a length of wire into a helix having a plurality oi staple bridge forming sides and a plurality of staple leg forming sides,

causing the convolutions of said helix to adhere through. the passage of an electric current through the wire of said helix, and cutting said helix along said leg forming sides to form a plurality of staples from each convolution of said helix.

3. The method of producing staple strips which consists in winding a length of wire .coated with an adhesive substance into a helix having a plurality of staple bridge forming sides and a plurality of staple leg forming sides, and cutting said helix along said leg forming sides to form a plurality of staple strips each consisting of a plurality of staples retained together by said adhesive substance. I

4. The method of producing staple strips which consists in winding a length of wire coated with aheat meltable adhesive substance into a helix having a plurality of staple bridge forming sides and a plurality of stapleleg forming sides, applying heat to said helix to me'ltsaid adhesive coating to cause the convolutions of the helix to adhere, and cutting said helix along said leg forming sides to form a plurality of staples from each convolution of said helix.

5. The method of producing staple strips which consists in winding a length of wire into a helix having a,plurality of staple bridge forming sides and a plurality of staple leg forming sides, there being angular bends between said sides, imparting a non-straight shape to portions of the convolutions of said helix between said bends, and cutting said helix along said leg forming sides to form a plurality of staples from each convolution of said helix.

MAX VOGEL. 

